Congratulations, I hope you are feeling well and have a trouble free, happy time.
I'm not a medic but I'll give you my opinion for what it's worth. Whatever you decide to do I think you should double check with a health care professional to see if they think it's wise.
What I would be most worried about is nicotine. I've heard that it causes problems for the dot that might last them a lifetime. NRT is only recommended when absolutely necessary and I think for health evaluation purposes, in your case you should consider using liquid nicotine as NRT. This is not in any way satisfactory but it's the only
thread we have about NRT safety -
http://www.e-cigarette-forum.com/forum/health-safety-e-smoking/3598-nicotine-safety.html
As I said, I'm not a medic and bear in mind there have been no real human trials of eliquid so this is just opinion. Personally I wouldn't worry about propylene glycol, glycerine or alcohol but you might want to think about flavourings and whether they are safe to inhale.
I would go for it, if it gets you off tobacco it's likely to be an improvement even if it's not ideal. Try to stick with zero nicotine and decide on what you think about flavourings. If you can bear it then straight propylene glycol and/or glycerine are probably even better. You could still enjoy the habit of 'smoking' without nic and flavour. There is a little bit of information about flavourings and health here -
http://www.e-cigarette-forum.com/fo...oking/2666-inhaling-flavouring-chemicals.html
Ideally you could achieve a nice calm, relaxed, happy state without any props but if you must have something then try to minimise the risks.
There really isn't any information on the forum about pregnancy so if you would like to start a thread and share your findings it might help others with the same concerns.
All the best, I hope everything goes well.